This invention relates to suspension systems used to provide support to railway vehicles during transportation, and more particularly to a pneumatic suspension system for railway repair machines that is selectively operable during transportation.
Shock and vibrations are substantial in railway and commercial truck transportation. The sudden bouncing or vibrations during railway and truck travel disrupts passenger comfort, can damage cargo and can also reduce the operational life of the vehicles themselves. Thus, trains and trucks require adequate support or cushioning during transportation to reduce the disruptive shock and vibrations caused to the vehicle. To control the disruptive shock and vibrations, conventional transportation vehicles use mechanical springs or air springs to support the vehicle""s body over the chassis. Air springs derive their suspension properties from resilient air-filled bladders, are primarily used in the trucking industry and are located near the front and rear axles of a truck body.
Similarly, railway repair machines tropically have a suspension system that utilizes mechanical springs for support. Like the air spring systems, conventional mechanical spring systems are designed to reduce shock and vibration to the operator and machine components during transportation. When the repair machines reach their destination, the machines stop and prepare for operation. In operation, the mechanical suspension system must be manually locked out to prevent swaying or rocking during a repair or maintenance procedure. If the machine is allowed to rock or sway, it could cause damage to the track portion being repaired or allow the machine to lift off the track and derail, or provide poor and/or inconsistent rail maintenance. Rocking or swaying during rail repair makes it more difficult for the operator to accurately control the repair operation.
Therefore, the operator must manually rigidly lock the suspension system in place prior to operation by placing a solid object or suspension cylinder between the machine frame and the suspension arm underneath the mechanical spring. The cylinder holds the frame and the suspension arm apart and prevents the machine from rocking during repair procedures because the mechanical springs are not supporting the frame.
A related disadvantage of rigidly locking the suspension is that since the frame is locked at the four points of contact with the rail, uneven rails tend to reduce the stability of the machine due to loss of wheel contact with the rail.
Thus, a major disadvantage of the conventional railway repair machine suspension systems is that the mechanical spring system must be manually locked in place by the operator before beginning any work. Subsequently, the suspension system must be manually unlocked prior to transportation. The manual locking and unlocking of the mechanical suspension system on the railway repair vehicles takes substantial time and effort by the operator.
Therefore, there is a need for a suspension for a railway repair vehicle which does not require manual locking down prior to performance of the maintenance operation.
Accordingly, it is the primary object of the present invention to provide an improved suspension system for railway repair machines that is selectively operable and that greatly increases the stability of the repair machine during railway maintenance procedures.
It is another object of this invention to provide an improved suspension system for railway repair machines that is easy to control and requires minimal operator manipulation to activate and deactivate the system.
It is a further object of this invention to provide an improved suspension system for railway repair machines that increases operator safety and comfort during transportation of the machine, and minimizes rocking and swaying of the machine during immobilization and operation of the machine for railway repair procedures.
The above-listed objects are met or exceeded by the present improved suspension system which provides selective support between the frame and chassis of a railway repair machine. The system is inflatable when the machine travels along the railway and is deflatable to provide a more secure base for a rail maintenance operation.
More specifically, the present suspension system is for a railroad maintenance machine having a frame and a chassis, where the su:pension system is selectively operable during transportation of the machine. The suspension system includes a suspension mechanism for providing suspensive support to the frame relative to the chassis and operable between a first position, when the suspension mechanism is substantially inflated for transportation of the machine, and a second position, when the suspension mechanism is substantially deflated for conducting railroad repairs and maintenance. A control mechanism allows operator selection of the suspension mechanism between the first and second positions.
Thus, when selectively deflated by the operator, the present suspension mechanism provides a relatively rigid relationship between the chassis and the frame. Consequently, railway repairs can be made from a !;table operational base.